Salvage workers prepare the Costa Concordia cruise ship on Aug. 23 in the waters of the Tuscan island of Giglio. The massive cruise ship has lain partially submerged after a disaster on Jan. 13, 2012, that killed 32 people.

"It's an old nautical term ... from the days of sailing ships," says Nick Sloane, the South African salvage master in charge of the Costa Concordia removal operation. "In those days, they could use the leverage of the mast and the sail booms to assist" in raising a ship.

The cost of the operation, insurance companies warn, could exceed $1 billion.

A Complicated Undertaking

Weighing more than 114,000 tons, the ship rests precariously on two sloping underwater granite reefs. Sloane's crew has pumped 18,000 tons of cement to fill the gaps between the reefs and support the hull.

With the use of cranes and winches, giant steel chains — each link weighing some 750 pounds — have been looped under the vessel to help pull it upright.

To protect the bow of the Concordia, it's been cradled in a specially built buoyancy tank that Sloane says is similar to a collar brace for an injured person.

"Before you rotate the patient you want to support the neck, so this is going to support her bow as we roll her over," he says. "That will reduce all the impacts on her spinal structure members, and that is going to save the bow during the parbuckle operation."

The most challenging part of the preparatory work was drilling into the reef to build an artificial seabed on which the upright vessel will rest: six steel platforms each the size of 1 1/2 football fields.

The granite off Giglio Island is the hardest rock known to man, Sloane says.

"It's like trying to drill with a hand drill on a plane of glass at a 45-degree angle and it just skips off the glass," he says. "The drill just wants to kick off the whole time away from the granite."

Crews, Officials Confident Of Success

With the ship chained to the mainland on one side and to steel pylons on the other, dozens of pulleys will slowly pull and rotate the ship upright at a rate of about 9 feet per hour.

The operation is expected to be extremely noisy from the wrenching and fracture of some parts of the internal structure.

But the salvage team is confident the external structure will remain intact — so confident, in fact, that there is no Plan B if something goes wrong.

Franco Gabrielli, head of Italy's Civil Protection agency, came to Giglio Wednesday to brief residents in a town hall meeting.

"The salvage team and the international commission of engineers and experts overseeing the Concordia removal have given me all the necessary assurances that the operation is ready to start," he said.

Massimo Luschi is the head engineer who gave the all-systems-go. He dismisses concerns that the parbuckling could lead to an environmental disaster. He says that along with the fuel, most of the toxic substances on the ship have already been pumped out. Every accessible crack and porthole, he says, has been sealed.

"We have no worries whatsoever," Luschi says. "I dare say this is the most monitored section of the sea around Italy. We have kept this area under careful surveillance every single day since the shipwreck."

Giglio residents, Luschi adds, should be warned that the rising of the ship will unleash an intense stench of rotten eggs — the result of rotting food onboard a ship carrying more than 4,000 people.

Ghosts Of The Costa Concordia

But despite the experts' show of confidence, there is one very big question mark: No one knows the exact condition of the side of the ship lying on the reef, which juts into the hull by as much as 30 feet.

Once upright, workers will look for the bodies of the two people believed to be still trapped under the ship.

Throughout their work, Sloane says, his crew has been well aware of the many ghosts of the Costa Concordia.

"When you stand onboard and you actually look and you feel the passenger ship, it is a strange feeling, because you can see through some of the portholes, and you see the cabin, exactly how it was," he says. "People don't forget that. Every day it's there; you are aware of it."

The salvage operation is being financed by insurance companies for ship owner Costa Crociere, which in turn is owned by the U.S. giant Carnival.

The trial of the ship's captain, Francesco Schettino, charged with manslaughter and abandoning ship before all passengers were evacuated, resumes later this month.

In a controversial ruling that sidestepped criminal charges, Costa, as Schettino's employer, admitted some responsibility and was ordered to pay $1.3 million.

Copyright 2014 NPR. To see more, visit http://www.npr.org/.

Transcript

AUDIE CORNISH, HOST:

Next week, one of the largest maritime salvage operations ever attempted is slated to get underway. The Costa Concordia luxury liner smashed into a jagged reef of an Italian island almost two years ago. 32 people were killed. Since then, the vessel has been lying on its side, an unsightly wreck visible for miles around. NPR's Sylvia Poggioli reports on a new effort to roll the ship back upright, all in one piece.

SYLVIA POGGIOLI, BYLINE: Waves lapping against the pier on the island of Giglio drown out the distant drone of the massive machines, cranes and barges surrounding the shipwreck. The Costa Concordia is the length of three football fields and as high as an 11-story building. Its carcass is like an alien from outer space that plopped down alongside the wooden dinghies moored in the small fishing port.

For 14 months, 500 workers of 26 different nationalities have been hard at work, preparing to rotate the ship upright, what's known in the trade as parbuckling.

NICK SLOANE: It's an old nautical term even from days of sailing ships. And in those days, they could use the leverage of the mast and the sail booms to assist.

POGGIOLI: Nick Sloane is the South African salvage master in charge of the removal operation. The ship, weighing more than 114,000 tons, rests precariously on two sloping underwater granite reefs. Giant steel chains, each link weighing some 750 pounds, have been looped under the vessel to help pull her upright. To protect the ship's bow, it's been cradled in a specially built buoyancy tank, similar to a collar brace for an injured person.

SLOANE: Before you rotate the patient, you want to support the neck. So this is going to support her bow as we roll her over, and that will reduce all the impacts on her spinal structure members. And that's going to save the bow during the parbuckle operation.

POGGIOLI: The most challenging part of the preparatory work was drilling into the reef to build an artificial seabed on which the upright vessel will rest: six huge steel platforms. The granite off Giglio Island, Sloane says, is the hardest known to man.

SLOANE: It is like trying to drill with a hand drill on a plane of glass at a 45-degree angle, and it just skips off the glass. The drill bit just wants to kick off the whole time away from the granite.

POGGIOLI: With the ship chained to the mainland on one side and to steel pylons on the other, dozens of pulleys will slowly pull and rotate the ship upright at a rate of about nine feet per hour. The operation is expected to be extremely noisy from the wrenching and fracture of some of the ship's internal structure. But salvage team is confident the ship will remain intact, so confident that there's no plan B if something goes wrong.

Franco Gabrielli, head of Italy's Civil Protection agency, came to Giglio Wednesday to brief residents in a town hall meeting.

FRANCO GABRIELLI: (Through translator) The salvage team and the international commission of engineers and experts overseeing the Concordia removal have given me all the necessary assurances that the operation is ready to start.

POGGIOLI: Massimo Luschi is the head engineer who gave the all systems go. He dismisses concerns that the ship's rotation could lead to an environmental disaster, saying that along with the fuel, most of the toxic substances on the ship have already been pumped out. Every accessible crack and porthole, he says, has been sealed.

MASSIMO LUSCHI: (Through translator) We have no worries whatsoever. I dare say this is the most monitored section of the sea around Italy.

POGGIOLI: But despite the experts' show of confidence, there's one very big question mark. No one knows the exact condition of the side of the ship lying on the reef, which juts into the hull by as much as 30 feet. Once upright, workers will look for the bodies of the two people believed to be still trapped under the ship. Throughout their work, Sloane says, his crew has been well aware of the many ghosts of the Costa Concordia.

SLOANE: When you stand on board and you actually look and you feel the passenger ship, it's a strange feeling because you can see thru some of the portholes and you see the cabin, exactly how it was. People don't forget that. Every day, I mean, it's there. You're aware of it.